The present invention relates to medical transfer and storage devices wherein a major component is formed of a cyclic olefin polymer and a second component fused to such cyclic olefin polymeric component. A preferred embodiment of this invention is a sealed sterilized container and closure assembly, such as a sealed vial or transfer set, wherein the closure or collar is fused on the open end of the vial.
The development of cyclic olefin polymers has suggested the use of such polymers for the manufacture of medical devices because such polymers are transparent, exhibit excellent chemical resistance, and may be sterilized by autoclaving or the like without damage. However, the Applicant has found that certain polymers will chemically react with and fuse to cyclic olefin polymers at elevated temperatures required for sterilization, limiting the use of cyclic olefin polymers for medical devices, including medical transfer and storage devices. The Applicant proposes to utilize this apparent disadvantage to fuse a component of a medical storage or delivery device to a cyclic olefin polymeric component, such as a closure on a vial formed of a cyclic olefin polymer.
A conventional vial for storing a medicament, drug or vaccine includes an open end, a radial rim portion surrounding the open end, and a reduced diameter neck portion adjacent the rim portion. The vial is conventionally sealed with an elastomeric stopper which generally includes a tubular portion inserted into the neck of the vial and a planar rim portion which overlies the vial rim. The stopper is normally secured to the vial with a thin malleable metal cap, such as aluminum. The aluminum cap includes a tubular portion which surrounds the rim portions of the stopper and vial, an inwardly projecting annual portion which overlies the rim portion of the stopper and a distal end portion which is crimped or deformed radially into the neck portion of the vial, beneath the vial rim portion. Because aluminum is malleable, the collar accommodates build-up of tolerances of the dimensions of the stopper and vial rim. The dimensions and tolerances of standard vials and stoppers are set by the International Organization for Standards (ISO).
The rim portion of the aluminum cap which covers the stopper rim portion may be closed, in which case the aluminum cap is removed by “peeling” the aluminum cap from the vial. A pre-slit tab located in the mid-portion may be provided which overlies the vial rim, permitting the cap to be torn away from the top and peeled from the vial prior to use. This method of sealing a vial has several disadvantages. First, the tearing of the metal cap creates sharp edges which may cut or damage sterile gloves and cut the person administering the medicament, drug, or vaccine, thereby exposing both the healthcare worker and the patient to disease and contamination of the content of the vial. Second, tearing of the aluminum cap generates metal particles which may also contaminate the content of the vial. The dangers associated with the tearing of an aluminum cap have been solved in part by adding a “flip-off” plastic cap. The plastic cap is then removed by forcing the flip-off cap away from the aluminum collar, which tears an annular serrated portion surrounding the central opening and exposing an opening in the collar for receipt of a hypodermic needle or the like. This embodiment reduces, but does not eliminate the possibility of tearing the sterile gloves of a health care worker. More importantly, however, aluminum dust is still created which may contaminate the contents of the vial. It is also important to note that metallic dust is created by forming and affixing an aluminum collar to the vial because aluminum dust is created in forming the aluminum collar, crimping the collar and removing the flip-off plastic cap. Aluminum collars are also used to secure a fluid transfer set on medical vials. Transfer sets may be utilized, for example, to transfer liquid from a syringe to a vial, such as to reconstitute a dry or powder drug in a vial, by adding a diluent or solvent. The reconstituted drug may then be withdrawn from the vial by a syringe. The inner surface of the transfer set may be part of the drug fluid path and the aluminum collar or ring may bring particles in the sterile room where the drug is added to the vial or into the fluid path contaminating the medicament, drug or vaccine.
More recently, the Applicant has developed plastic closures for vials and transfer sets and a method of crimping a plastic closure on a vial as disclosed in a co-pending application. However, this method of securing a closure on a vial requires a separate crimping step prior to sterilization, such as autoclaving. The method of fusing a cap or closure to a vial or other medical container formed of a cyclic olefin polymer of this invention solves these problems by utilizing the apparent “disadvantage” of cyclic olefin polymers which presently limit the use of such polymers for sterilizable storage and delivery devices.